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Abstract At low-temperatures a gas of bosons will undergo a phase transition into a quantum state of matter known as a Bose–Einstein condensate (BEC), in which a large fraction of the particles will occupy the ground state simultaneously. Here we explore the performance of an endoreversible Otto cycle operating with a harmonically confined Bose gas as the working medium. We analyze the engine operation in three regimes, with the working medium in the BEC phase, in the gas phase, and driven across the BEC transition during each cycle. We find that the unique properties of the BEC phase allow for enhanced engine performance, including increased power output and higher efficiency at maximum power.
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Empirical analysis of losses from business-email compromise
We examine approximately nine months of data on losses from business email compromise (BEC) reported to the FBI’s Internet Crime Complaint Center in 2017. We describe the empirically observed loss distribution.We study differences in the amounts attempted stolen when the attacks were successful or not.We show that money stolen and transmitted internationally is less likely to be recovered. We also find, somewhat surprisingly, that illicit transfers to in-state banks are also more likely to succeed. Finally, we study state-level differences among BEC target selection and asset recovery.
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- Award ID(s):
- 1652610
- PAR ID:
- 10256908
- Date Published:
- Journal Name:
- Proceedings of the APWG Symposium on Electronic Crime Research
- ISSN:
- 2639-4286
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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